Sterile Filtration
Sterile Filtration — The process of passing a solution through a 0.22-micron filter to remove bacteria and particulates, used when preparing peptide solutions for cell culture.
What Is Sterile Filtration?
Sterile filtration is the removal of microorganisms from a solution by passing it through a membrane with a pore size of 0.22 µm (220 nm). Bacteria, fungi, and yeast are retained by the membrane while the peptide solution passes through. It is the standard sterilization method for heat-sensitive peptide solutions that cannot survive autoclave temperatures (121°C).
Filtration Technique for Peptides
- Membrane material: PVDF (low protein binding) or PES (polyethersulfone) for peptides. Avoid cellulose acetate (high binding losses)
- Pre-wetting: Rinse the filter with buffer before filtering the peptide solution to reduce adsorptive losses
- Volume: Use syringe filters (13-25 mm) for < 10 mL; vacuum or pressure filtration for larger volumes
- Recovery: Measure peptide concentration before and after filtration to quantify adsorptive losses, especially for hydrophobic peptides
Quality Assurance
Post-filtration integrity testing (bubble point test) confirms the membrane was not damaged during filtration. Filter certificates document endotoxin levels, extractables, and bacterial retention validation for the specific membrane lot used.
Frequently Asked Questions
What is Sterile Filtration?
The process of passing a solution through a 0.22-micron filter to remove bacteria and particulates, used when preparing peptide solutions for cell culture.
Why is Sterile Filtration important in peptide research?
Sterile Filtration is a fundamental concept in laboratory as it relates to peptide science. It directly influences experimental design, compound characterization, and the reliability of research outcomes across biochemistry and molecular biology disciplines.
Authority Sources
- Sterile Filtration on Wikipedia
- Search Sterile Filtration on PubChem (NIH)
- Research articles on ScienceDirect